Synthesis of Ferromagnetic Filled Carbon Nanotubes and their Biomedical Application

摘要:

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Especially during last years, fundamental discoveries of various species and
modifications of carbon nanotubes have stimulated research on their application including in
human medicine. The success of these applications depends significantly on the physical,
chemical and biological properties of the carbon nanotubes and their supplements.
In our presentation we report on the synthesis of Fe-filled carbon nanotubes, their structural
and magnetic properties and propose novel types of such functionalised and filled multiwalled
carbon nanotubes with various advantages for an application in human medicine,
especially in anti-tumour therapeutic concepts.
These nanotube structures represent multi-functional nano-scaled containers for different
medical treatments including magnetically guided hyperthermia. Furthermore these chemical
inert and stable carbon nanocontainer can be act as a new drug delivery carrier system. In
principle, both, a filling of nanotubes by an open-fill-close process or an attachment of
argents on the outside of the carbon nanotube is possible.

摘要: Nano-structured carbon nitride film, which is a new sensor material, has been prepared by
facing target magnetron sputter for microsensor applications. Surface morphology, surface roughness
and bonding structures of the films were investigated by EDS, SEM, AFM and FTIR spectroscopy.
The growth rate of film is about 2.2 um/hr, and grain size and RMS roughness are about 320 nm and
0.9 nm, respectively. The impedance of micro-humidity-sensor, which was fabricated by the
conventional semiconductor fabrication process including lift-off technique, changed 95.4 kΩ to 2
kΩ in the relative humidity range of 5 % to 95 %.

摘要: Carbon nanotube is a new kind of carbon material. Synthesis of carbon nanotubes from V-type pyrolysis flame is a kind of novel technique. It needs simple laboratory equipments and normal atmosphere pressure. The V-type pyrolysis flame experimental system is introduced. Carbon source is the carbon monoxide which is carried to the middle pipe of V-type pyrolysis flame combustor. Heat source is from acetylene /air premixed flame. Pentacarbonyl iron, served as catalyst, is transported by spray- pyrolysis method into the burner. The carbon nanotubes were characterized by scanning electron microscope and transmission electron microscope. The diameter of carbon nanotubes is approximate 20nm and its length is dozens of microns. The impact of the temperature, reactant composition and catalyst was analyzed to reveal the rule of carbon nanotube growth. Carbon nanotubes with good form and less impurity can be captured when the temperature was from 800°C to 1000°C and carbon monoxide/hydrogen/helium mixed gas flow was supplied. The effective diameter of pentacarbonyl iron nanoparticles is approximate from 5nm to 20nm in the process of carbon nanotube formation. Mechanism of carbon nanotube base on the V-type pyrolysis flame method was proposed. The carbon “dissolved-proliferation-separate out” theory can be used to explain how the pentacarbonyl iron catalyses carbon monoxide to form carbon nanotubes.

摘要: Pyramid sharp pyrolysis flame is a new method for carbon nanotubes synthesis. Oxy-acetylene flame outside the frustum of pyramid sharp reactor provides the necessary high temperature circumstance for carbon nanotubes synthesis, while inside the interior mixture of CO, H2, He, and iron pentacarbonyl (Fe(CO)5) is heated. CO is used as the source of carbon, Fe(CO)5 as the source of catalyst precursor. Special structure of the frustum of pyramid sharp reactor makes the oxy-acetylene flame folded gradually above the reactor. And it meets the condition that the interior mixture which has reacted initially under high temperature and will flow out of reactor avoids exposing to air completely and burning abundantly. Immersing a sampling substrate into the incomplete burning flame can gain carbon nanotubes. By adjusting the distance between the oxy-acetylene flame jet and the synthesis area, achieved the purpose that just changing one factor of synthesis or pyrolysis temperature while the other one constant, then respectively studied the effects of them on experimental. The perfect synthesis temperature in experimental is about 595°C, while the pyrolysis temperature is about 1000°C.

摘要: Surface modification of carbon fibers(CF) by physicochemical methods directs an attractive approach for improvement of metal uptake from solutions. We investigated pretreatment of carbon fibers by HNO3 with different time on absorption of catalysts, which is related to the coverage of carbon nanotubes (CNTs) grown on Carbon fibers. The effects of surface modifications on the properties of carbon fibers were studied by X-Ray photoelectron spectroscopy. The modifications bring about variation in the chemical properties. The modification increased a large number of surface functional groups such as hydroxyl and carbonyl. The HNO3 modification increases the catalysts absorption. The coverage of CNTs on CF increases with pretreatment time, which was studied by SEM.

摘要: Carbon nanotubes based on anodic aluminum nano-templates embedded with different metal catalysts were synthesized and the influence on the morphology of the products of the gas flow rate and the reaction time was closely investigated. The samples were characterized by field-emission scanning electron microscope. The results confirmed that the products are carbon nanotubes with controllable size and the morphology of the products were different with the different reation conditions.